* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
  color: #e4e4e7;
  min-height: 100vh;
  line-height: 1.6;
}

.container {
  max-width: 700px;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

header {
  text-align: center;
  margin-bottom: 2rem;
}

.back {
  display: inline-block;
  color: #818cf8;
  text-decoration: none;
  margin-bottom: 1rem;
  font-size: 0.9rem;
}

.back:hover {
  text-decoration: underline;
}

h1 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
  color: #fff;
}

.subtitle {
  color: #a1a1aa;
  font-size: 1rem;
}

main {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.input-section {
  background: rgba(255, 255, 255, 0.05);
  border-radius: 12px;
  padding: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: #d4d4d8;
}

input[type="number"] {
  width: 100%;
  padding: 1rem;
  font-size: 2rem;
  font-family: 'SF Mono', Monaco, 'Courier New', monospace;
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 8px;
  color: #fff;
  text-align: center;
  -moz-appearance: textfield;
}

input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

input[type="number"]:focus {
  outline: none;
  border-color: #818cf8;
  box-shadow: 0 0 0 3px rgba(129, 140, 248, 0.2);
}

.primary-btn {
  width: 100%;
  margin-top: 1rem;
  padding: 0.875rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
  background: linear-gradient(135deg, #6366f1 0%, #818cf8 100%);
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
}

.primary-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
}

.primary-btn:active {
  transform: translateY(0);
}

.result-card {
  background: rgba(255, 255, 255, 0.05);
  border-radius: 12px;
  padding: 1.5rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  text-align: center;
}

.result-card.hidden {
  display: none;
}

.status-header {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  margin-bottom: 1rem;
}

.status-emoji {
  font-size: 3rem;
}

.status-info {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.status-code {
  font-size: 2.5rem;
  font-weight: 700;
  font-family: 'SF Mono', Monaco, 'Courier New', monospace;
  line-height: 1;
}

.status-name {
  font-size: 1.25rem;
  color: #a1a1aa;
}

.status-message {
  font-size: 1.1rem;
  color: #d4d4d8;
  margin: 1rem 0;
  font-style: italic;
}

.status-meta {
  margin-top: 1rem;
}

.category-badge {
  display: inline-block;
  padding: 0.375rem 0.875rem;
  border-radius: 9999px;
  font-size: 0.8rem;
  font-weight: 500;
}

.category-badge.informational { background: #3b82f6; color: #fff; }
.category-badge.success { background: #22c55e; color: #fff; }
.category-badge.redirect { background: #f59e0b; color: #000; }
.category-badge.client-error { background: #ef4444; color: #fff; }
.category-badge.server-error { background: #dc2626; color: #fff; }

.categories-section {
  margin-top: 1rem;
}

.categories-section h3 {
  font-size: 0.85rem;
  color: #a1a1aa;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 1rem;
}

.category-group {
  margin-bottom: 1.25rem;
}

.category-title {
  font-size: 0.9rem;
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  margin-bottom: 0.5rem;
}

.category-title.informational { background: rgba(59, 130, 246, 0.2); color: #60a5fa; }
.category-title.success { background: rgba(34, 197, 94, 0.2); color: #4ade80; }
.category-title.redirect { background: rgba(245, 158, 11, 0.2); color: #fbbf24; }
.category-title.client-error { background: rgba(239, 68, 68, 0.2); color: #f87171; }
.category-title.server-error { background: rgba(220, 38, 38, 0.2); color: #fca5a5; }

.codes-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.code-btn {
  padding: 0.5rem 0.875rem;
  font-size: 0.85rem;
  font-family: 'SF Mono', Monaco, 'Courier New', monospace;
  background: rgba(255, 255, 255, 0.05);
  color: #d4d4d8;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 6px;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.1s;
}

.code-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: #818cf8;
  color: #fff;
  transform: translateY(-1px);
}

footer {
  text-align: center;
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  color: #71717a;
  font-size: 0.875rem;
}

footer a {
  color: #818cf8;
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

/* Color code based on status */
.result-card[data-category="informational"] .status-code { color: #60a5fa; }
.result-card[data-category="success"] .status-code { color: #4ade80; }
.result-card[data-category="redirect"] .status-code { color: #fbbf24; }
.result-card[data-category="client-error"] .status-code { color: #f87171; }
.result-card[data-category="server-error"] .status-code { color: #fca5a5; }